When making an attack, the attacker rolls a d20 as usual. Any roll of 5 or lower is an automatic miss, regardless of modifiers. The defender has the option to dodge (which uses up their next action) or to parry.

To parry, the defender rolls a d20. If the defender rolls higher than the attacker, then they have successfully parried the attack, otherwise the attack is successful. In the event of a tie, the defender always wins.

While holding a shield, a defender may also Block. Blocking works similarly to parrying, but the defender has advantage.

If the attacker is successful in landing a blow, the damage first goes to the defenders AC. The defender's AC must drop to zero before any damage can be done to HP. (If a defender has 1 AC left, and they take 5 damage, the remaining 4 damage does not carry over to HP.)

Defenders cannot parry against dex saves. In these instances, you make the save as usual, or you may attempt to dodge. A successful dodge takes up your action but you take no damage. You can not dodge any other form of save.